Anthracnose & Turf

Cause

• The Colletotrichum graminicola fungus causes anthracnose on turf grasses. The fungus lives and thrives in rotting organic matter in grass. Fungal growth is favored by prolonged warm temperatures of 80 to 90 degrees Fahrenheit. Grass that is growing poorly or is culturally stressed is more prone to infection.

Damage

• Early symptoms of disease include the appearance of irregularly shaped patches of brown grass on lawns. Damaged areas are between 2 inches to 1 foot in diameter. Grass blades show tan or brown spots with black fruiting bodies on dead grass. Mature grass is affected first. New grass stays green longer.

Control

• Grow grass in well-drained soil and keep turf in good health. Use disease-resistant varieties and obtain grass from reliable sources. Avoid fertilizing grass during drought or high heat. Dethatch and aerate lawn regularly. Recommended fungicides include polyoxin D and strobilurin.